Team Update #11

[Gary Dillard]

Here's how I plan to do it:

We'll pressurize the system to cutoff with the pressure switch (around 115-120 psi), then back off the jam nut and turn the valve until it relieves. We'll go back the other way a little (1/4 turn?), jumper across the pressure switch, and watch the gauge to see where it relieves. We'll iterate from there.

... We used this method and it worked OK. You could hear the valve venting and see the pressure slow down at ~125, it went up to ~135 or less and held there until we released the pressure switch jumper; then it vented back to ~125 and stayed there. With the hysteresis on the valve I think that's about the best you can expect.

[Peter Matteson]

Originally Posted by Daniel_LaFleur

Hook up the pneumatic system with just the compressor hooked to the pressure relief valve, a dump valve (manual) and a pressure gage.

power the compressor from a battery (use a fused line for safety). Bring the pressure to ~130 PSI. The relief valve should release pressure when it hits ~125 PSI.

If it doesn't then adjust the valve to release and then retry (poppit valves are notorious for not being very stable nor re-seating very well).

An FYI for everyone who tests this way. The reseating pressure of the valve is usually 10-20% below the release pressure. After you make your adjustments vent the sytem, then represurize for the next test to verify you actually are at the set point and not significantly below it.

Also hysterisis on the spring will mean your valve could pop +/- a few psi and still completely meet the manufacturers spec. I suggest looking at this value to see what it is so you don't chase your tail on the variation.

[Dancin103]

Originally Posted by eugenebrooks

Is the withholding allowance PARTS, or completed MECHANISM?

My reading of the rules, and consistency with past rules, leans
towards PARTS, but it is not entirely clear this year.

Eugene

Fabricated Items.